Copied a file from the server to the laptop. The servers are connected to each other via Gigabit ethernet and to the router via 100Mb ethernet. The router is a TP-Link 300Mb router.
I averaged 2.5MB/s speed for a 1.1Gb file.
I then went into the setting and changed the bandwidth capability to 20/40Mhz and my connection is now showing as 11.0Mbs in the network panel. Tried to copy the same file and the network bombed out almost straight away and lost the connection to the router and network. The card reconnected to the network and downloaded the same test file at around 2.8-3MB/s with constant pauses. The final download speed was 2.55Mb/s. Speedtest.net 31/17Mb/s
Plugging in the TP-Link TL-WN821N adapter gives the following results (I appreciate the 821N is a 300Mb adapter):
6.5-7Mb/s download from the network (no pauses)
Speedtest.net 63/18Mb